General DescriptionThe AAT3105 is a charge-pump based, current-source white LED driver capable of driving one to four LEDs up to 30mA, each. It automatically switches between 1x mode and 2x mode to maintain the highest efficiency and optimal LED current matching.The AAT3105 charge pump’s 1x mode (bypass mode) has very low resistance, allowing LED current regulation to be maintained with input supply voltage approaching the LED forward voltage.LED brightness is controlled using a universal PWM interface. The AAT3105 is available in a Pb-free, 2x2mm 10-lead SC70JW-10 package

Features*Drives up to 4 LEDs at up to 30mA each*Automatic Switching Between 1x and 2x Modes*0.85MHz Switching Frequency*Linear LED Output Current Control*Universal PWM Interface*±10% LED Output Current Accuracy*±3% LED Output Current Matching*Low-current Shutdown Mode*Built-in Thermal Protection*Automatic Soft-start*Available in 2x2mm SC70JW-10 Package

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General DescriptionThe AAT3340 is a low-noise, constant-frequency charge pump DC/DC converter that uses a dual-mode load switch (1x) and fractional (1.5x) conversion to maximize efficiency for white LED applications.The AAT3340 is capable of driving 4 white LEDs at a total of 80mA from a single 2.7V to 5.5V input.The current sinks may be operated individually or in parallel while driving higher-current LEDs. A low external parts count (two 1μF flying capacitors and two small 1μF capacitors at VIN and VOUT) makes the AAT3340 ideal for small battery-powered applications.Analogic Tech’s Simple Serial Control (S2Cwire) digital interface is used to enable, disable and set current to one of 32 levels for the LEDs.The AAT3340 is equipped with built-in short-circuit and over-temperature protection.The soft-start circuitry prevents excessive inrush current at start-up and mode transitions.The AAT3340 family is available in Pb-free, space-saving TSOPJW and TDFN33 packages, and operates over the -40°C to +85°C ambient temperature range.

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General DescriptionThe AS3685 is low noise high efficiency capacitive charge pump with 1:1, 1:1.5 and 1:2 operating modes in a small 3x3mm DFN10 or a tiny 2x1.5mm WL-CSP (Wafer Level Chip Scale Package) package. It can drive one flash led at up to 700mA current. It supports flash/torch and indicator mode for the flash led.Additionally the AS3685 limits the flash time automatically to protect the flash LED.

General DescriptionThe TC962 is an advanced version of the industry standard TC7662 high voltage DC-to-DC converter.Using improved design techniques and CMOS construction, the TC962 can source as much as 80 mA versus the 7662’s 20 mA capability.As an inverter, the TC962 can put out voltages as high as 18V and as low as 3V without the need for external diodes. The output impedance of the device is a low 28Ω (with the proper capacitors), voltage conversion efficiency is 99.9%, and power conversion efficiency is97%.The low voltage terminal (pin 6) required in some TC7662 applications has been eliminated. Grounding this terminal will double the oscillator frequency from 12 kHz to 24 kHz. This will allow the use of smaller capacitors for the same output current and ripple, in most applications. Only two external capacitors are required for inverter applications. In the event an external clock is needed to drive the TC962 (such as paralleling), driving this pin directly will cause theinternal oscillator to sync to the external clock.Pin 1, which is used as a test pin on the 7662, is a voltage reference Zener on the TC962. This Zener (6.4V at 5 mA) has a dynamic impedance of 12Ω and is intended for use where the TC962 is supplying current to external regulator circuitry and a reference is needed for the regulator circuit. (See Section 3.0 “Applications Information” Applications Information).The TC962 is compatible with the LTC1044, SI7661 and ICL7662. It should be used in designs that require greater power and/or less input to output voltage drop. It offers superior performance over the ICL7660S.

DESCRIPTIONThe SP6682 is a current regulated charge pump ideal for converting a Li-Ion battery input for driving white LEDs used in backlighting color displays or cell phone camera flash applications. The charge pump automatically switches between X1.5 and X2 modes based on the program-mable VMODE voltage, providing improved efficiency over traditional methods using charge pump doubler followed by LDO. This input voltage threshold can be externally programmed by a resistor divider network for optimized efficiency at specific output voltages and currents. The SP6682 operates with an internal 600kHz clock, which reduces switching noise and improves VOUT ripple.Output current or voltage can be accurately regulated by modulating the switcher between the charge pump and output capacitor. In shutdown mode, the IC disconnects the output from the input and draws less than 1.5μA current. The SP6682 is offered in a 10-pin MSOP package, and a small 10-Pin DFN Package.

GENERAL DESCRIPTIONThe TC7660S is a pin-compatible upgrade to the Industry standard TC7660 charge pump voltage converter. It converts a +1.5V to +12V input to a corresponding -1.5V to -12V output using only two low-cost capacitors, eliminating inductors and their associated cost, size and EMI. Added features include an extended supply range to 12V, and a frequency boost pin for higher operating frequency, allowing the use of smaller external capacitors. The on-board oscillator operates at a nominal frequency of 10kHz. Frequency is increased to 45kHz when pin 1 is connected to V+. Operation below 10kHz (for lower supply current applications) is possible by connecting an external capacitor from OSC to ground (with pin 1 open). The TC7660S is available in both 8-pin DIP and 8-pin small outline (SOIC) packages in commercial and extended temperature ranges.